Lidar system based on visible-near infrared-shortwave infrared light bands

Abstract

A lidar system based on visible-near infrared-shortwave infrared light bands comprises a light source sub-system, a light receiving sub-system and a signal collecting and processing sub-system, and adopts a laser light source having a supercontinuum spectrum laser comprising the three bands of visible, near infrared and shortwave infrared light. The lidar system conveniently and effectively achieves hyperspectral measurement of three bands of visible, near-infrared, and shortwave infrared lights without needing to replace the laser light source, increasing the capability of detecting target spectrum information and application range, providing more accurate measurement results and post-processing algorithms, and strengthening the capability of simultaneously detecting visible-near infrared-shortwave infrared ligh bands of a lidar system.

1 . A lidar system based on visible-near infrared-shortwave infrared light bands, comprising:
 a light source sub-system configured to generate supercontinuum spectrum laser comprising three bands of visible light, near-infrared light and shortwave infrared light, wherein part of the supercontinuum spectrum laser is emitted as detection light to a detection target and forms an echo, and part of the supercontinuum spectrum laser is used as a main wave of the lidar and generates a main wave electrical signal;   a light receiving sub-system configured to receive an echo reflected by the detection target, divide the echo into a visible-near infrared echo and a shortwave infrared echo, and generate a visible-near infrared echo electrical signal and a shortwave infrared echo electrical signal; and   a signal collecting and processing sub-system configured to control the light source sub-system to emit the supercontinuum spectrum laser, and receive the visible-near infrared echo electrical signal, the shortwave infrared echo electrical signal and the main wave electrical signal, and perform analysis and processing to obtain three-dimensional information and spectral information of the detection target.   
     
     
         2 . The lidar system of  claim 1 , wherein the light source sub-system comprises a laser light source, a beam collimator, a beam splitter, and a main wave photoelectric sensor;
 wherein the laser light source emits the supercontinuum spectrum laser comprising the three bands of the visible light, the near-infrared light, and the shortwave infrared light;   the supercontinuum spectrum laser is incident on the beam splitter after being collimated by the beam collimator, part of the light is transmitted through the beam splitter and emitted as the detection light to the detection target, part of the light is reflected by the beam splitter, and the reflected light is received by the main wave photoelectric sensor as a main wave of the lidar, and the main wave photoelectric sensor generates the main wave electrical signal.   
     
     
         3 . The lidar system of  claim 2 , wherein the light receiving sub-system comprises a receiving lens, a wavelength splitter, a first diffraction grating, a first photoelectric sensor, a second diffraction grating, and a second photoelectric sensor;
 wherein an echo formed after the detection light is reflected by the detection target is received by the receiving lens, and an echo passing through the receiving lens is incident on the wavelength splitter, and the visible-near infrared echo is reflected by the wavelength splitter, the shortwave infrared echo is transmitted through the wavelength splitter;   the visible-near infrared echo is incident on the first diffraction grating, the first diffraction grating divides the visible-near infrared echo into optical bands arranged in accordance with wavelengths, the optical bands are incident on the first photoelectric sensor, and the first photoelectric sensor converts the visible-near infrared echo into the visible-near infrared echo electrical signal; and   the shortwave infrared echo is incident on the second diffraction grating, the second diffraction grating divides the shortwave infrared echo into optical bands arranged in accordance with wavelengths, the optical bands are incident on the second photoelectric sensor, and the second photoelectric sensor converts the shortwave infrared echo into the shortwave infrared echo electrical signal.   
     
     
         4 . The lidar system of  claim 3 , wherein the signal collecting and processing sub-system comprises a first digital collecting card, a second digital collecting card, and a computer;
 wherein a signal input end of the first digital collecting card is connected to signal output ends of the main wave photoelectric sensor and the first photoelectric sensor, and a signal input end of the second digital collecting card is connected to signal output ends of the main wave photoelectric sensor and the second photoelectric sensor, the signal output ends of the first digital collecting card and the second digital collecting card are connected to the computer, and a signal output end of the computer is connected to the laser light source.   
     
     
         5 . The lidar system of  claim 4 , wherein the computer generates a trigger signal that controls the laser light source to emit the supercontinuum spectrum laser;
 the first digital collecting card and the second digital collecting card receive the main wave electrical signal as a main wave trigger signal, perform digital sampling on the main wave trigger signal, and send the sampled main wave trigger signal to the computer;   the first digital collecting card digitally samples the visible-near infrared echo electrical signal and sends the sampled visible-near infrared echo signal to the computer;   the second digital collecting card digitally samples the shortwave infrared echo electrical signal and sends the sampled shortwave infrared echo signal to the computer; and   the computer performs analysis and processing based on the received sampled main wave trigger signal, the sampled visible-near infrared echo signal and the sampled shortwave infrared echo signal, to obtain the three-dimensional information and the spectral information of the detection target.   
     
     
         6 . The lidar system of  claim 2 , wherein the light receiving sub-system comprises a receiving lens, a wavelength splitter, a first diffraction grating, a first photoelectric sensor, a second diffraction grating, and a second photoelectric sensor;
 wherein an echo formed after the detection light is reflected by the detection target is received by the receiving lens, and an echo passing through the receiving lens is incident on the wavelength splitter, and the shortwave infrared echo is reflected by the wavelength splitter, the visible-near infrared echo is transmitted through the wavelength splitter;   the shortwave infrared echo is incident on the first diffraction grating, the first diffraction grating divides the shortwave infrared echo into optical bands arranged in accordance with wavelengths, the optical bands are incident on the first photoelectric sensor, and the first photoelectric sensor converts the shortwave infrared echo into the shortwave infrared echo electrical signal; and   the visible-near infrared echo is incident on the second diffraction grating, the second diffraction grating divides the visible-near infrared echo into optical bands arranged in accordance with wavelengths, the optical bands are incident on the second photoelectric sensor, and the second photoelectric sensor converts the visible-near infrared echo into the visible-near infrared echo electrical signal.   
     
     
         7 . The lidar system of  claim 6 , wherein the signal collecting and processing sub-system comprises a first digital collecting card, a second digital collecting card, and a computer;
 wherein a signal input end of the first digital collecting card is connected to signal output ends of the main wave photoelectric sensor and the first photoelectric sensor, and a signal input end of the second digital collecting card is connected to signal output ends of the main wave photoelectric sensor and the second photoelectric sensor, the signal output ends of the first digital collecting card and the second digital collecting card are connected to the computer, and a signal output end of the computer is connected to the laser light source.   
     
     
         8 . The lidar system of  claim 7 , wherein the computer generates a trigger signal that controls the laser light source to emit the supercontinuum spectrum laser;
 the first digital collecting card and the second digital collecting card receive the main wave electrical signal as a main wave trigger signal, perform digital sampling on the main wave trigger signal, and send the sampled main wave trigger signal to the computer;   the first digital collecting card digitally samples the shortwave infrared echo electrical signal and sends the sampled shortwave infrared echo signal to the computer;   the second digital collecting card digitally samples the visible-near infrared echo electrical signal and sends the sampled visible-near infrared echo signal to the computer; and   the computer performs analysis and processing based on the received sampled main wave trigger signal, the sampled visible-near infrared echo signal and the sampled shortwave infrared echo signal, to obtain the three-dimensional information and the spectral information of the detection target.   
     
     
         9 . The lidar system of  claim 3 , wherein the computer is connected to an upper computer, and the computer stores the received sampled main wave trigger signal, the sampled visible-near infrared echo signal and the sampled shortwave infrared echo signal and sends them to the upper computer, and the upper computer performs subsequent analysis and processing to obtain the three-dimensional information and the spectral information of the detection target. 
     
     
         10 . The lidar system of  claim 3 , wherein the wavelength splitter is a lens with increased transmittance and high reflectivity.